Robot navigation is a critical component of mobile robots. In non-autonomous modes, robots are typically controlled using direct commands through keyboard, joystick, or mouse. However, in certain cases, such as robotic wheelchairs, a disabled patient might not be able to use these methods. In this paper, a speech recognition based robot navigation is presented in which the user can navigate the robot in a grid environment though voice commands. The results are evaluated in a simulation based environment.

The social development of drones is progressing rapidly, and they are beginning to be used in many industrial fields. Autonomous position estimation in non-GPS environments aims to expand the usability of unmanned aerial vehicles (UAVs) where GPS signals are unavailable, such as underground, indoors, or areas obstructed from satellite signals. This is particularly relevant for search and rescue operations during disasters and complex industrial applications. This research proposes a method that integrates multiple sensors, including RGBD cameras, IMUs, LiDAR, and GNSS, enabling the UAV to autonomously select and utilize the optimal sensor data for precise self-localization. We develop algorithms for sensor data fusion, environmental perception, and sensor selection and switching to ensure advanced autonomy in unmanned aerial systems. This framework is designed to enhance the operational capabilities of UAVs in GPS-denied environments, broadening the scope of their application.

RTK-GNSS positioning enables centimeter-level accuracy. Incorrect FIX determinations may exist in the positioning results, making it impossible to obtain accurate location. In this study, we propose two methods for detecting wrong FIX using point clouds obtained from 3D Lidar, posture data from IMU, and RTK-GNSS positioning data. One is extracting shape features based on persistent homology from the point clouds and comparing them. Another is comparing the overlap ratio of point cloud data measured at each positioning location. To demonstrate the effectiveness of the proposed methods, they were compared with the results of the Ratio Test.

We propose a recovery method using GNSS from the failure of LiDAR-based mobile robot self-localization. The method guides a robot to an area where the robot can receive GNSS information without self-localization. In the guide algorithm, a two dimensional LiDAR is used for finding the area. Through experiments, we confirmed that an actual robot in kidnapped states can receive GNSS information after navigation with our method and reset self-localization. This means our method contributes enhancing the robustness of outdoor mobile robot navigation.

This paper investigates using Neural Radiance Fields (NeRF) to enable autonomous navigation simulations without the need for actual robots. NeRF's strength lies in its ability to render photorealistic images, promising a solution to the long-standing challenge of the domain gap between simulation and real-world environments. We present findings that validate the effectiveness of a NeRF-simulated environment for training a reinforcement learning policy. Once trained in the NeRF environment, this policy can navigate an actual robot in the real world.

We propose a novel odometry method utilizing posture information from Flexible Mono-tread mobile-Track(FMT). This method presupposes the path-following capability of subsequent joints to the leading joint expected of FMT. Therefore, we investigate the mobility characteristics of FMT and evaluate the feasibility of the proposed method.

Self-position estimation technology is important for autonomous robots and other applications. However, most of the 2D LiDAR systems used for such applications have low sampling frequency and resolution, and are not suitable for high-precision and high-speed control. Therefore, we have proposed the measurement system that combines 2D LiDAR and one-dimensional laser rangefinder. The system uses a 2D LiDAR to detect walls and a one-dimensional laser rangefinder to point at the wall to detect the relative position of the wall. In conventional system, it is difficult to detect the relative angle between the wall and the measurement system. In this paper, we propose a system that detects the relative angle between the mesument system and the wall by adding a one-dimensional laser rangefinder, and conduct experiments to confirm its operation. As a result, we found that the system can detect the distance and angle to the wall.

We are conducting research to realize industrial operation of mobile robots. For position estimation, we adopted a method that uses two-dimensional information, keeping industrial use in mind and considering cost. Using this method, I participated in the Nakanoshima Extra Challenge 2024, completed the task, and completed the race. Through this experiment, we will discuss the characteristics of our position estimation method.

We develop an indoor robot localization method using wireless distance sensors. To take into account the case where the distance sensor measures the reflected path due to obstacles, we propose a method to estimate the reflected path at the same time and use it for position estimation.

When conducting ascending and descending experiments outdoors to verify the performance of space elevator climbers, it is not possible to accurately evaluate the performance of the space elevator climber because it is not possible to conduct the experiments under uniform conditions due to weather and other factors. In addition, long-distance and endurance tests are difficult to conduct due to the limited lifting and lowering distance. In this study, we will develop an indoor lifting and lowering test apparatus capable of long-distance lifting and lowering tests to solve the above problems.

Robots are required to operate in areas where there are many obstacles or where there is no stable ground. To realize this by flying freely in the air, we designed and created a wire-driven aerial mobile robot with high-output wire winders and large-diameter tires. To realize dynamic motion, we designed a high-power wire winder with a maximum tension of 350[N] and a winding length of 15[m]. The large-diameter tire was designed for use as a tire on the ground and for attitude control in the air. In addition, large rubber was used on the outside of the tires to reduce the fall impact.

The purpose of this study is to develop a super-directional loudspeaker with a variable audible range using a parabolic reflector. This paper proposes a cam-based mechanism for changing the shape of the parabola and a method for changing the audible range by an equivalent point source irradiating the parabola.

In this paper, an ankle and foot model for efficient plantar flexion, named the passive energy storage mechanism, is proposed. It is known that the human ankle joint can sometimes function like a stiff spring depending on the situation. In such cases, compensating for external forces solely through motor performance can be considered inefficient. The proposed mechanism is equipped with a tendon-driven spring as a passive element for storing elastic energy. The ankle joint can rotate freely although it is equipped with a spring during non-ground contact, but the spring is stretched during ground contact. It is possible to utilize the energy stored in the spring during the kicking motion and achieve efficient plantarflexion movement by harnessing disturbances.

This paper proposes a two-axis differential joint mechanism using a flexible teethed belt is proposed, and the mechanism is designed and fabricated. Experiments were conducted to measure the angular velocity and torque of the proposed mechanism to demonstrate the remote drive performance of the mechanism. The experimental results showed that the transmission performance of torque was low, but the angular velocity was correctly transmitted.

We proposed and verified a novel suspension mechanism that combines a constant-force spring and a compression spring, which enables the robot to pass over uneven terrain, such as deep recesses, where a conventional suspension mechanism would cause the wheels to float, although the force pressing down on the ground is weak when passing over the recesses or bumps. We proposed and verified a suspension mechanism that reduces the floating of the wheels and distributes the load on the robot as a whole to each wheel, so that the robot can pass stably over uneven terrain such as deeper depressions and higher bumps.

In this research, we will implement an angle sensor based on the strain gauge principle at the joints of a micro multi-legged robot composed of an origami frame. There is a great advantage of being able to directly read joint angles, and we evaluated the characteristics of angle feedback control.

This paper investigates and presents the impact forces acting on the end-effector and joints when a link-stiffened multi-degree-of-freedom mechanism collides with a highly rigid object. In particular, impacts on the order of a few hundred μs are treated, and impacts sharper than a nail drive are investigated. The purpose of this paper is to clarify the extent to which impact forces acting on joints are mitigated by mechanical backdriving of the joints . The aim is to develop a robot that can perform a wide range of impact tasks, such as forging and percussion testing. In the experiments, a passive three-joint link mechanism was fabricated, and a stainless steel hammer head attached to a hand end was used to strike a stainless steel plate. The experimental results show that a mechanism with high backdrivability is capable of impact mitigation.

In this paper, we introduce a novel linear drive mechanism featuring shape adaptability. It is well-known that power transmission, whether through rotation or linear motion, inevitably forms a ”loop of force lines” due to the action of force and counterforce. If the shape of these can always be matched, it is theoretically possible to decouple the relationship between power and its shape. In other words, the path of power transmission can be driven arbitrarily by external forces. Based on this principle, we propose ”NestChain,” which incorporates a chain within a chain. This unique structure, capable of extracting force along the power transmission path, enables continuous linear motion along adapted shapes.

The authors have previously developed a lightweight and low-friction power transmission mechanism called the passive 3D wire transmission mechanism. In this study, the relationship between the diameter of passive pulleys and the power transmission efficiency of this mechanism was measured to enhance its lightweight and low-friction properties. Utilizing the measurement results, suitable wire types and passive pulley diameters were selected for the wire-driven manipulator SAQIEL.

Japan became a super-aging society, and the number of wheelchair users will increase further than now. Although Japan have recently promoted barrier-free public buildings, there are a lot of bumps that prevent them from going their ways, so they often need to assistant in moving outdoors. As the way to solve such problems we study on the mobile robot that can climb steps by using transformable wheels, work on the development of the automatic control technique. In this paper, we design the mechanism of the elliptic transformable wheels in consideration of creating by 3D Printer and advanced materials. Also, we devise control method to achieve automatic going up and down, used RGB-D camera as the way to measure steps. The result shows we design 3D model of the elliptic transformable wheels and RGB-D camera measure steps accurately.

One of the satellite-type high-performance countercurrent chromatographs used as a reference in this study performs three rotations of the three axes, the solar axis (angular velocity ω1), the planetary axis (ω2), and the satellite axis (ω3), according to the equation ω1=ω2+ω3. Next, the J-type high-speed counter-current chromatograph system performs a double rotation consisting of the solar and planetary axes according to the following equation: ω1 = ω2. The trajectory of the rotational motion and the acceleration at separation in these cases are derived and compared. In addition, the MPS method (Moving Particle Semi-Implicit method) is used as a fluid analysis to evaluate the degree of separation due to its motion.

Topology optimization is a technique that has attracted considerable attention in recent years as a method for mathematically calculating optimal structures that would not be conceivable by humans. On the other hand, topology optimization requires iterative calculations for optimization, which can be computationally demanding depending on the target, and the resulting structures are often complex and difficult to process. In particular, when optimizing a structure such as a manipulator that is long in one direction, the computational load increases and the structure cannot be fabricated in one piece. In this study, we investigate a method for designing a manipulator using the method of topology optimization with periodic structures in series, which is effective for the design of structures that are long in one direction, as proposed in our previous study.

In this research, to internally manufacture a multi-stage planetary gear mechanism that is compact and lightweight, we proposed a design methodology using a stereolithography 3D printer. We designed a three-stage planetary gear mechanism consisting of a carrier with a sun gear, planetary gears, brackets, two types of internal gears, and a crank. We printed those parts using a stereolithography 3D printer, assembled them with the motor, and manufactured the planetary gear mechanism. Furthermore, we applied voltage to the motor and verified the operation of the planetary gear mechanism. As a result, we successfully manufactured a multi-stage planetary gear mechanism that has a module of 0.1, a diameter of 5.6mm, a mass of 0.17g, a transmission ratio of 1:139, and rotates at 44rad/s.

Interpersonal touch interactions, such as handshakes and high-fives, can indicate a child’s healthy growth. Thus far, we have developed bracelet-type devices that quantify the hand touches using the inter-body area network technology. This study aims to improve the device’s wearability and current transmission function for the network. To this end, we designed the wristbands using soft conductive fabric, which expands the electrode layout. This paper reports an experiment to validate the effects of the electrode layout on the current transmission function by measuring the signal-to-noise(S/N) ratio of 25 electrode layouts, with five levels of electrode area and five levels of distance between electrodes. The results showed that the S/N ratio increases as the electrode area and distance between electrodes increase. Notably, the effect of the electrode area expansion is more moderate than that of the distance between electrodes.

This paper reports on a three-dimensional shape optimized seesaw-type force sensor with a double helix structure. The proposed force sensor comprises a force-receiving elastic body and a displacement-detecting laser displacement meter. The elastic body, where the structure is shape optimized, consists of a seesaw-type beam with the force application part and the displacement detection part on each side. The force is calculated by multiplying the beam’s displacement and the spring constant of the beam. The beam is a seesaw-type by extending beams to the left and right from a double helix to decrease the spring constant compared to the simple beam structure. The proposed force sensor has a three-dimensional shape optimization of the double helix of the beam to selectively increase the stiffness of the beam in the direction of compression, where the same rotational spring constant. The beam printed by an FDM 3D printer has a curved cross-section at the double helix.

In this paper, we propose a measurement system that can simultaneously acquire the displacement of the finger pad and the penetration into the groove when tracing on rough surfaces. The authors proposed a measurement system for acquiring only the displacement of the finger pad surface. Experiment using this system revealed vibrations on the surface of the finger pad. These vibration phenomena appear to depend on penetration of the finger pad surface into the grooves. However, conventional measurement systems could not simultaneously measure the penetration into the groove. The result of the measurement with this system proposed in this paper showed that the finger pad surface was deeply penetrated in the grooves when the width of the grooves were 1.5 mm and 2.0 mm.

It is known that the secretion of oxytocin from the brain helps people feel a sense of security and happiness. To make people feel secured and happy, we look to present a sensation similar to hand shaking．We also try to provide an acupressure massage by placing a contact object created by a 3D printer, and thermal stimulation by a heater embedded in a handprint model that would be effective for presenting healing. We prototyped a silicon handprint device, and the healing effect was verified both by EEG measurement results and questionnaires with a five-point scale. Based on the results of evaluation experiments, we presume that this handprint device may have the potential to promote oxytocin secretion, thereby enhancing feelings of security and happiness. Furthermore, the application of acupressure massage and thermal stimulation could potentially accerelate stress reduction and relaxation.

This research is developing and studying a remote hand robot application that transmits force sensation to a data glove, suitable for grape farms in Nabari City. This will reduce the burden on farmers and prevent the decline of grape farmers in Nabari City. Currently, we are verifying whether a pressure sensor can detect the sense of force so as not to damage the grapes.

High-resolution tactile sensors are essential for dexterous manipulation with a robot hand, and optical sensors such as GelSight have attracted attention in recent years. However, there are no optical sensors that have a simple point-contact shape, such as a human finger, which is round at the top and flat at the bottom of the finger. In this study, we developed an optical tactile sensor that incorporates the Human contact shape of a human fingertip and confirmed that it was easy to do manipulation and can acquire high-definition textures.

Detecting lumps inside the skin by palpation is an important diagnostic method in medicine. In this study, the ability of a tactile sensor developed using MEMS technology to detect lumps in a breast model was evaluated. It is shown that even small lumps, which are difficult for humans to detect can be detected in the indentation test. By performing out palpation with the breast model, data can be collected for the practical application of palpation devices on humans. In addition, the accuracy of the tactile sensor can be ascertained by knowing its ability to identify lumps, which can be applied and improved in various fields.

We propose a method to generate vibration sensations automatically following the motion of a person in a video so that anyone can create content with motion sensations easily. We have already confirmed that the impact and presence of the videos increased when vibration stimuli generated from sound effects were added to the jumping motion. In this study, we propose a method of presenting a sensation linked to a performer’s movement using vibration stimuli to express differences in skill in movement. The method uses human pose estimation to detect the motion of a person in a video. Then, it generates vibration waveforms based on the perceived intensity proportional to motion. Subject experiments verify the effectiveness of the proposed method.

This study proposes a flexible and submersible tactile function based on conductive powder and radon conversion. It consists of a conductive powder, an elastic membrane bag containing an insulating liquid, and electrodes. The tactile function uses the change in volume resistivity of the conductive powder, which changes with load. Thus, it is achieved by measuring the impedance of the conductive powder between all pairs of eight electrodes. Since the conductive powder serves as the wiring, it allows large deformations and does not break. Furthermore, our approach is very compact. We incorporated this approach into a universal vacuum gripper to obtain pressure distribution. We will ultimately plan to develop a high-resolution pressure sensor that can be measured underwater.

In haptic feedback using focused ultrasound, a technique has been proposed that involves creating an ultrasound focal point using a spherical surface without the need for phase control. This method is efficient as each transducer faces directly toward the focal point, but it has a limitation – the focal point remains fixed due to the ultrasonic transducers being attached to a static sphere. This study introduces a method to move the focus in the depth direction by dynamically changing the curvature of the spherical surface to which the transducers are attached. We built a device that can adjust curvature using a servo motor, confirming its capability to relocate the focus position. The study also investigates the softness presentation using the created device.

This paper reports on a three-dimensional waterflow sensor that utilizes multiple absolute pressure sensors arranged on a polyhedral origami circuit. The distribution of pressure on a sphere is influenced by and correlates complexly with both the speed and direction of flow. Consequently, we developed a spherical sensor on which multiple sensor elements are arranged three-dimensionally using a folded origami circuit. Subsequently, we immersed the fabricated device in a water tunnel and conducted experiments to assess its response as well as collect ground truth. We adopted neural network model to predict different speeds and angles, and then evaluated the predictive capabilities of the model. The results demonstrated that the proposed device was distinctly able to predict different velocities and confirmed its scalability for 3D waterflow sensing.

The general mechanical parts have small irregularities on the surface and the potential to affect the assembly of the products. In mechanical design of robots, mobility, and home appliances, surface features related to mechanical function are more essential elements. The products development process should be shortened in the product development field because problems in product development is the increase of time and cost due to the improvement of quality. Therefore, CAE simulations have been conducted at the design stage using ideal surface topography without surface irregularities and deviations. In this study, the multiscale method we have developed in previous study was improved to generate more realistic surface model. The generated surface models were compared with actual machined surfaces based on surface profile parameters.

In recent years, development toward fully automated driving has been underway. In order to realize fully automated driving of automobiles, it is necessary to understand the surrounding conditions, and in snowy areas such as Toyama Prefecture, it is necessary to understand the depth of snow accumulation. Therefore, the LiDAR used for fully automated driving of automobiles is operated as a snow depth gauge, and by having each automobile measure the amount of snow cover, an environmental map is also created at the same time. In addition, self-position estimation is also performed simultaneously with the creation of the environmental map, and the results are intended to be reflected in automatic driving.

In 3D scene understanding tasks using LiDAR data, constructing training data poses a challenge due to its high annotation cost. To this end, annotation-free simulator-based training has recently been gaining attention, while the domain gap between simulators and real environments often leads to decreased generalization performance. This paper introduces a Sim2Real domain adaptation method that mitigates the domain gap by reproducing realistic raydrop noise onto labeled simulation data using deep generative models, enhancing its applicability to real-world scenarios. We demonstrate the effectiveness of our approach in multiple segmentation tasks.

SLAM technology is an effective means for mobile robots to identify the position. SLAM by a single robot causes large errors, however, in such environment with few feature points, as lunar or planetary surface. Therefore, this paper proposes a new distributed cooperative SLAM method using multiple robots, which is effective even in environments with few feature points.

3D maps are important for autonomous and remote operation of robots and drones to achieve the missions of a service in a known space. However, the accuracy of 3D point cloud maps varies greatly depending on the method used to generate them. In this study, we propose a method to compare 3D point cloud maps with different accuracy. Eigenvectors and ICP register the 3D objects to be compared. Convert to voxel representation with different voxel sizes to compare two models. Evaluate the F-measure (precision-recall relationship) of each voxel size to check the overlap of the two models. This method allows us to compare 3D maps of different accuracies, although the evaluation values will vary depending on the voxel size, partly due to noise effects.

Dysphagia often causes aspiration pneumonia which is currently the sixth leading cause of death in Japan. In the clinical site, videofluorography (VF) is often used to visualize the laryngeal elevation in the throat but requires the X-ray equipment and knowledges of well-practiced medical doctors to assess the dysphagia. In the present study, we propose a method to allow easy, quantitative, and contactless measurement of the laryngeal elevation using a laser displacement sensor. Specifically, new experimental system and analytical method were developed to stably measure the laryngeal elevation. The pilot experiment showed a possibility that laryngeal movements similar to the previous studies using VF can be obtained using the proposed method.

Gait disturbances in Parkinson’s disease (PD) are highly susceptible to changes in the patient’s surrounding environment. Yet it is often challenging to elicit this symptom in a standard clinical examination room. The present study proposes a method using virtual reality (VR) to experimentally induce freezing of gait (FoG) in PD patients. In details, we asked PD patients and healthy old people to walk along a virtual corridor where virtual obstacles were placed in various conditions. The experimental results demonstrated that the proposed system can experimentally induce the FoG only in PD patients. Further, analysis of walking data allowed to detect characteristic gait changes in PD patients with the FoG. These findings suggest that the proposed VR-FoG manipulation and evaluation system is useful to develop a new diagnostic method for the gait disturbances in PD patients.

The Broken Escalator (BE) phenomenon is a unique experience that people have unnatural feelings, walking behavior or postural changes when stepping onto a broken escalator, although the escalator is completely stopped. It is thought that previous experience of stepping onto a driving escalator modulates human motor control resulting in the BE phenomenon. Thus, several previous studies have suggested that the visual information of an escalator, which includes previous experience, strongly contributes to the BE phenomenon. In the present study, we tested if a virtual escalator displayed on a head-mounted display can induce the BE phenomenon. In details, walking behavior and subjective assessment on the virtual escalator and floor during the experiment were analyzed to reveal the potential of virtual reality to the BE phenomenon.

In recent years, plush robot therapy has been developed and put into practical use. However, these robots have a problem in that actuators and sensors are built-in, compromising the softness of the plush. Therefore, this paper proposes a tactile sensor for soft plush robots. We created a fabric touch panel and an algorithm that can distinguish human stroking motions. By using a capacitive-type fabric touch panel, it is possible to detect where a person has touched the fabric. The algorithm distinguishes stroking motions using frequency analysis. We installed the created fabric touch panel on a plush robot wearing a powered garment and operated the plush robot according to the stroking direction.

In recent years, with the increase in the elderly population, there is a need for training programs that meet individual needs. However, with conventional training programs, it is difficult to customize them in consideration of individual needs and interests, and issues remain in maintaining motivation and achieving effective training. Therefore, we aim to develop a system that allows trainers to provide effective training programs by combining games and AI. We conducted experiments using actual camera sensor. Experiment results show that the proposed method is effective for personal training. The results of this research are expected to contribute to improving the quality of life of the elderly and people who require training.

This paper describes measuring ground reaction force (GRF) of fruit flies using a biaxial force plate. The proposed sensor has spring structures displacing in x, z axis direction. Using two laser displacement meters, it is possible to measure the GRF of fruit flies in both anterior and vertical directions, which has been difficult due to its small size. By using a glass plate as the material, accurate measurements can be made no matter where the measurement target walks on the plate as well as high sensitivity. The spring constants in x, z axis were approximately 10 N/m, and the force resolutions were less than 1/50 of the target’s weight. Measuring the GRF in the both anterior and vertical directions of a fruit fly showed a constant value, indicating walking stability.

Stress caused by the misalignment of movements in cooperative work with robots has become a problem. In this study, we used the synchronization phenomenon to induce the human work rhythm by sound, and estimated and evaluated stress based on heart rate variability when a change in sound is perceived. Subjects performed a tapping task as a periodic task in a cooperative work environment. Heart rate was measured during the experiment, and the stress state was estimated from the heart rate variability. Results: It is not clear whether it is possible to induce stress while suppressing its increase under the conditions of the present study. However, it was suggested that it is possible to induce the subjects’ work rhythm under certain conditions.

The aim of this study is to quantitatively evaluate the motor function of the upper limb from motion data measured using inertial sensors. Joint angles obtained from a rigid body link model calculated from the posture of the inertial sensor were used as feature quantities. By analyzing the joint angles using Extended Dynamic Mode Decomposition (EDMD), a linear state-space model was constructed in which the variation of the joint angles was taken as the observed value. By analyzing the observation matrices of each obtained mode, we propose that it is possible to evaluate upper limb function according to the role of motion.

In this report, the indoor temperature and the wind speed are changed in the automobile air conditioning system in seasons with temperature differences, and the subject's biological information is measured to investigate the relationship with human subjectivity. Then, subjectivity regarding comfort is quantitatively evaluated to clarify the relationship between comfort value, air conditioning system wind conditions, and human biological information.

Distracted driving is the second most common cause of traffic accidents in recent years, after improper driving operation. Reducing seat-seat fatigue during driving, which is one of the causes of distracted driving, has become an important issue for reducing traffic accidents. The purpose of this study was to elucidate the relationship between seating behavior and seating muscle fatigue during prolonged driving by drivers. Long-hour driving experiments were conducted using a driving simulator, posture measuring device, and accelerometer. Fatigue was evaluated subjectively by the experimental collaborators and objectively by using biometric data. As a result, it was verified that postural shape and postural change had a significant influence on seating fatigue and that the number of body movements was deeply related to seating fatigue.